1. Field of the Invention
The present invention relates to a container for a disk, which contains a disk for recording a data signal such as audio and video, particularly, relates to a container having a mechanism of being able to hold an optical disk having a center hole securely and able to remove the disk from and insert the disk into the container easily.
2. Description of the Related Art
Currently, two major types of containers, which contain a disk such as a digital versatile disk (DVD) of recording a large capacity of audio and video information, are utilized. One of the containers is a parallelpipedic case for a compact disk (CD). A shape of disks other than a CD disk such as a DVD disk is identical with that of a CD disk, so that a constitution of such a parallelpipedic case for a CD disk is applied to a container for other disks than a CD disk.
However, it is hard to distinguish such a parallelpipedic case from that for a CD disk. Further, in a case of recording a movie, such a parallelpipedic case is small in dimension, so that a jacket or booklet introducing its contents is restricted dimensionally. Accordingly, a container dimensionally similar to a container for video software containing one videotape is also utilized.
It is important for this kind of container how to remove a disk from the container easily. Since a standard diameter of a disk is rather large such as 120 mm, it is hard for a person such as a child having smaller hands to handle such a disk. In a case of a disk such as a DVD disk, it is necessary for a DVD disk to increase a recording capacity in comparison with that of a CD disk. Therefore, some DVD disks adopt a construction of sticking two disks together. Further, a fastening and a removing means, which can release excessive stress to a DVD disk so as to prevent the DVD disk from peeling off, are required.
There provided various kinds of containers for a disk, which can hold a disk securely and assure easy removal of the disk when the disk is taken out from the container. U.S. Pat. Nos. 5,788,068 and 5,101,971 disclose the container for a disk.
According to U.S. Pat. No. 5,101,971, a container having a circumferential rib, which is divided into 9 pieces so as to coincide with a center hole of a disk, is provided. An outer diameter of the tip of the rib is designated to be slightly larger than the inner diameter of the center hole of a disk, so that the disk can be held securely and removed easily by using a spring effect of the circumferential rib. If engagement between the center hole of a disk and the rib is set for loosening so as to release the disk from overloading, the disk can easily be removed from the rib in the container. Accordingly, the disk moves freely inside the container and a surface of the disk recorded with a signal may be scratched. On the other hand, if the engagement is set for tightening not so as for the disk to come off, the disk can hardly be inserted or removed. Accordingly, the disk may be damaged when the disk is forced to be inserted or removed. In some cases, a signal recorded in the scratched disk or the damaged disk can be hardly reproduced due to scratches or damage.